Transformer-case.



No. 753,944. PATENTED MAR. 8,'1904. W. L. WATERS.

TRANSPORMBR CASE.

APPLIUATION FILED MAR. 5, 190s.

WiU-lesse ."UVEUTIIP MM William .WBTEVE UNITED STATES Patented March 8, 1904.

PATENT OFFICE.

TRANSFORMER-CASE.

SPECIFICATION forming part of Letters Patent N0. 753,944, dated. March 8, 1904.

Application led March 5, 1903. Serial No. 146,400. (No model.)

To all whom, it Ina/y concern:

Be it known that I, WILLIAM LAURENCE VVATERs, a subject of the King of England, residing at Milwaukee, in the county of M ilwaukee and State of Wisconsin, have invented a certain new and useful Improvement in Trans former-Cases, (Case No. 1,) of which the following is a full, clear, concise, and exact description, reference being had to the accompanying drawings, forming a part of this speciiication.

My invention relates to means for radiating heat from electrical instruments or machinery, and more particularly to the radiation of heat from so-called transformers.

My invention provides an improved form of casing for such transformers whereby a large cooling-surface is provided and whereby air-currents are induced to bring a large quantity of air into contact with the cooling-surfaces of the case.

As is well known` it is necessary to design commercial transformers of high eciency in such a manner that there is a considerable transformation of electrical energy into heat within the coils and cores of such transformers. In order that the temperature of a transformer may not rise to such a degree as to destroy or impair the insulation of the coils, it is necessary to provide means for conveying the heat from the transformer.

It is a common practice among those skilled in the art to place the core and coils of a transformer within a case of suitable conducting material-such, for instance, as cast-iron or other metalwand to fill this casing with oil in order to readily transmit to the casing by conduction or convection the heat generated in the transformer coreand coils. In order that the heat thus transmitted to the transformerecase may be rapidly radiated therefrom, it has been proposed to provide the surface'of the case with a large radiating-surface-such, for instance, as that provided by suitable corrugations or fins.

It is the purpose of my invention not so much to greatly increase the radiating-surface of the case as it is to provide means whereby air-currents may be induced to bring-a large quantity of air into Contact with the radiating-surfaces of the case.

My invention contemplates the provision of a transformer-case the shell of which contains tubular openings or chambers preferably opened at both ends and placed in a vertical position, whereby the heat radiated to the air confined within these tubes causes a circulation therethrough similar tothat in a chimney or smoke-stack.

My invention will be readily understood by reference to the accompanying drawings, in which- Figure 1 illustrates in end elevation a transformer-case constructed in accordance with my invention. Fig. 2 is a central cross-sectional view taken on line 2 2 of Fig. l; and Fig. 3 is a top view of the casing, showing the transformer core and coils in place.

I have illustrated a laminated iron-core provided with pancake windings or coils 5. The transformer core and coils form no part of my present invention, and any other suitable core and windings may be equally well employed. Surrounding this core and its coils is the tranformer-case comprising a bottom portion 6 and side walls 7 7, which together form an inner shell. Surrounding the inner shell 7 there is provided an outer shell 8, which may be integrally cast with said inner shell, the two shells being retained in proper relative disposition by the substantially radial webs 9 9. The spaces intervening between the inner and outer shells and adjacent webs 9 9 form tubes or chambers 10 l0, which it will be seen are open at both top and bottom. A suitable cover may be provided to protect the interior parts of the transformer. At Il and 12 are provided openings from which oil placed within the casing and surrounding the core may be drawn.

rIhe operationof a transformer fitted with my improved case may be described as follows: The heat generated in the transformer coils and core by the transformation of the electric currents passing therethrough is conveyed through the circulating medium within the casing to the inner shell thereof. While I have described the easing as being filled with oil, it will be apparent that air or any other circulating or conducting medium may be employed in place thereof. The inner and outer shells 7 and 8 and the intervening webs 9 9 are preferably cast together, so as to form v one integral piece of metal. The heat conveyed to the inner shell 7 is conducted through the webs toward the outer shell 8. rIhe air filling the tubes or chambers 10 is heated by contact with the surrounding surfaces and on account of its consequent decrease in density rises through the tubes and is rapidly replaced by cold air entering at the bottom of the tubes. It will thus be seen that a rapid movement of cold air is produced through each of the tubes, the phenomenon being similar to that of a chimney in which the heated air rises due to the upward pressure of the cold air on the outside. I have found that the rapid circulation of the air caused by the provision of inclosed tubes or chambers maintains the transformer at amuch lower temperature than where the case is provided with an equallylarge cooling area, but without the provision of special means for causing the circulation hereinbefore referred to.

Vhile I have thus described my invention as applied to transformers, it will be apparent that it may be applied with equal advantage to resistance-coils, reactance-coils, or the like. Many modifications may also be employed without departing from the spirit of the invention, and Ido not, therefore, wish to limit myself to the precise disclosure herein set forth; but,

Having described my invention, I claim as new and desire to secureA by Letters Patent l. In a device of the class described, the combination with an inclosing shell of heat-conducting material, of tubular openings extending through the material of said shell having -no communication with the interior of the inclosing' shell.

V 2. In a device of the class described, the combination with an inclosing shell of heat-conducting material, of parallel tubular openings extending through the material of said shell having no communication with the interior of the inclosing shell.

3.' Inadevice of the class described, the combination with a retaining-shell of heat-conducting' material, of tubular openings extending vertically through the material of said shell havingI no communication with the interior of the inclosing shell.

4. In adevice of the class described, the combination with a retaining-shell of heat-conducting material, of parallel tubular openings extending vertically through the material of said shell having no communication with the interior of the inclosing shell.

5. Ina device of the class described, the combination with an inclosing shell of heat-conducting material, of tubular chambers open at either end and surrounding said shell at the outside thereof and having no communication with the interior thereof.

6. In a device of the class described, the combination with an inclosing' shell of heat-conducting material, of vertical tubular chambers open at top and bottom, and surrounding said shell at the outside thereof and having' no communication with the interior thereof.

7. In a device of the class described, the combination with an inclosing shell of heat-conducting material, of parallel tubular chambers open at either end and surrounding said shell at the outside thereof and havingI no communication with the interior thereof.

8. In a device of the class described, the combination with an inclosing shell of heat-conducting material, of parallel vertical tubular chambers open at top and bottom and surrounding' said shell at the outside thereof and having no communication with the interior thereof.

9. In a device of the class described, the combination with an inclosing' shell of heat-conducting material, of a second shell surrounding said first shell, there being an intervening space between said shells having no communication with the interior of the inclosing shell and substantially radial webs interposed between said shells.

10. In a device of the class described, the combination with an inclosing shell of heatconducting material, of a second shell surrounding said lirst shell, there being' an intervening space between said shells having no communication with the interior of the inclosing shell and webs interposed between said shells.

l1. In a device of the class described, the combination with an inclosing shell of heatconducting' material, of a second shell surrounding said first shell, there being an intervening space between said shells, and substantially vertical webs interposed beween said shells and forming therewith parallel tubular chambers open at top and bottom andv having no communication with the interior of the inclosing shell.

l2. In a device of the class described, the combination with an inclosing shell 7 of heatconducting material, of an air-jacket 8 surrounding said inclosing shell, said air-jacket consisting of vertical tubular chambers 9, 9, said chambers being open at both ends to allow upward passage therethrough of cool surrounding air to carry with it the heat radiated into said chambers by said inclosing shell.

13. In a device of the class described, the combination with an inclosingL shell of heatconducting' material, of a second shell sur- IOO IOS

IIO

rounding said {i1-st shell, there being an intervening space between said Shells having no communication with the interior of the inelosing shell, and webs interposed between Said shells, said shells and said webs being east in one piece.

In witness whereof I hereunto subscribe my my naine this 22d day of February, A. D. 1903.

XVM. LAURENCE VATRS.

Witnesses:

XV. J. RICHARDS, CHAS. D. KNIGHT. 

